Loss of the urinary bladder, most commonly due to total cystectomy for muscle invasive carcinoma of the bladder, bladder dysfunction or bladder injury resulting in contraction, stiffness, spasticity or failure to store or to empty urine in a suitable manner are presently being treated with replacement or augmentation of the urinary bladder with intestinal tissue. These operations all have in common either the creation of an intestinal urinary conduit which drains urine continuously into a plastic bag on the patient's abdominal wall or the creation of an internal pouch constructed of intestinal tissue which stores urine inside the patient's abdominal cavity, urine being released either by catheter or newly learned techniques of urination which rely on coordinated abdominal muscle contraction and pelvic muscel relaxation.
Although the simplest of these forms of urinary diversion, the Bricker intestinal conduit or "ileal loop", is a standard and commonly performed surgical procedure, it is the least desirable. A bag must be worn on the abdominal wall which leads to social withdrawal and undesirable change in body image and has been shown to lead to long term damage of the kidneys from infection, obstruction and urinary stone formation.
There has been great interest and activity, as an alternative to this kind of diversion, in the construction of internal urinary reservoirs made of long segments of intestinal tissue. These operations are difficult to perform and usually can be done only in specialized medical centers. There is a considerable increase in risk to the patient. Normal urination will only be possible in a very small select group of men in whom the pouch can be sewn to the natural urinary outlet. In the remaining group of patients, which includes all women, the reservoir must be emptied by intermittent self catheterization introduced by way of an opening in the abdominal wall or the perineum. In addition to the potential for operative complications, the long term effects of redirecting a long segment of intestine from the intestinal tract to a reservoir which provides continuous contact with urine has yet to be determined. Disorders of digestive motility and absorption are common, absorption of urinary waste products through the intestinal wall is common, and the potential for development of cancer in the bowel segment in continuous contact with urine has been recognized, although the extent to which this may become a problem is yet unknown.
Although the use of extensive intestinal substitution and augmentation of the urinary bladder has become popular and safe in the hands of very specialized urological surgeons in a few national medical centers, the long term safety and efficacy remains to be determined, and there is every reason to believe that unexpected difficulties may arise within the next ten years following such reconstruction. There is thus a great need for a totally artificial urinary bladder which would allow patients to undergo complete replacement of the bladder without removal of any segment of the digestive tract.
Sowinski, French Patent No. 2,116,838, discloses an artifical bladder for implantation into the bladder's natural position and for connection to the two ureters and to the urethra of a patient. This bladder comprises a hollow elastic ball which can be elastically deformed to an inflated or to a deflated position under the presence of an auxiliary fluid, surrounding a deformable reception chamber for urine; a system of three internal valves, one of which operates in a direction opposite that of the other two; and a device to control the valves thereby controlling the auxiliary fluid. This bladder is complicated and relatively unreliable.
Chevallet, U.S. Pat. No. 3,953,897, discloses an implantable artificial bladder comprising a flexible plastic pouch which relies upon the internal tensions of the pouch wall in combination with external forces, including the force of the patient's abdominal muscles, to empty the pouch completely and rapidly. Chevallet relied upon the peristaltic effect of the ureter to prevent urine from flowing backwards. However, the combination of the internal tension of the artificial bladder wall and the external pressure of the patient's abdominal muscles could likely be greater than the peristaltic pressure of the ureter, particularly upon the discharging of the contents-of the bladder and therefore could cause urine to flow backwards through the ureters toward the kidneys.
Freier, DE No. 2,655,034, discloses an artificial bladder comprised of stiff plastics and valves to prevent the return flow of urine through the ureters and toward the kidneys.
It is the object of the present invention to provide an implantable artificial bladder and a method for the collection of, the storage of, or the discharge of biological fluids that will allow the patient to function in a nearly normal manner after the removal or the dysfunction of the natural bladder.
A primary advantage of the present invention is that the only pressure needed to empty the bladder is the pressure of a constant force stored energy means which is entirely contained within the implantable artificial bladder. The stored energy derives from the natural peristaltic pressure of the patient's ureter or ureters or from the normal pressure of an artificial ureter, which is utilized to fill the implantable artificial bladder. It is not necessary for the patient to apply any external pressure to fill or to empty the implantable artificial bladder. Indeed, he can not, due to the implantable artificial bladder's rigid shell. Another advantage of the present invention is that it does not have the severe energy demands of a pumped system. A further advantage is that the pressure exerted by the energy stored and used by this invention to empty the implantable artificial bladder does not exceed the normal back pressure or peristaltic pressure of the patient's ureter, and therefore, there will be no resultant backflow of urine through the ureter to the kidneys which would result in damage to those body parts.